This invention relates to apparatus for the protection of plumbing systems of recreational vehicles, vacation homes and the like against freezing in winter which has long been a source of inconvenience and concern for the owner.
A number of procedures have been utilized. In the simplest case, the water source is turned off and the pipes are drained by opening valves. In most cases, however, not all the pipes are properly inclined to permit total drainage and compressed air is commonly employed to blow out the remaining water. Even then, the air may pass over the surface of water lying in a nearly level water line so that sufficient water remains to cause trouble.